Hi I would suggest trying a known good board and replace your known good top board. then do factory reset then powerup to 10 voltage and wait for sounds to come up then lower and raise voltage and see if you hear the correect sounds then hit red button and attempt to run engine, are you sure your battery is charging if sound dies when you power up n down your battery is bad or your lower board is not charging you're battery! the boards can be repaired I can help you if you need assistance!
Alan